I have this call made on 2 x Raspberry Pi's in 2 different locations using 2 x different API keys and both frequently return the above. I ran the call manually and it took me 4 attempts to receive a complete json file.

I think this is another issue I am afraid. Anybody else seeing something similar.

Hi Brendan, we retrieve data based on ICAO codes (all of them - db of around 6500 ICAOs around the world). We noticed today errors with hourly forecast and 10-day forecast for over 100 locations). One example EGLC (London City Airport, was giving no data for hourly and partial data for 10-day for 20-30% of requests). but this happens for all locations. Thanks.